I want to buy a bike trailer for my 6 year old daughter so she can ride with me when I take my Giant Sedona out for a spin/charity ride/running errands. She has a Giant kids bike already...should I just buy a bar that attaches her bike to mine (and lifts her front wheel slightly off the ground)? Or should I spend more and get the trailer? I have another (younger) child who will use it after her, so I don't mind spending up to $200. Any suggestions???